Regulation of matrix metalloproteinase expression by estrogen in fibroblasts that are derived from the pelvic floor

Three-year outcomes of a randomized clinical trial of perioperative vaginal estrogen as adjunct to native tissue vaginal apical prolapse repair

BACKGROUND

As the muscular and connective tissue components of the vagina are estrogen responsive, clinicians may recommend vaginal estrogen to optimize tissues preoperatively and as a possible means to reduce prolapse recurrence, but long-term effects of perioperative intravaginal estrogen on surgical prolapse management are uncertain.

OBJECTIVE

This study aimed to compare the efficacy of perioperative vaginal estrogen vs placebo cream in reducing composite surgical treatment failure 36 months after native tissue transvaginal prolapse repair.

STUDY DESIGN

This was an extended follow-up of a randomized superiority trial conducted at 3 tertiary US sites. Postmenopausal patients with bothersome anterior or apical vaginal prolapse were randomized 1:1 to 1-g conjugated estrogen cream (0.625 mg/g) or placebo, inserted vaginally twice weekly for ≥5 weeks preoperatively and continued twice weekly for 12 months postoperatively. All participants underwent vaginal hysterectomy (if the uterus was present) and standardized uterosacral or sacrospinous ligament suspension at the surgeon's discretion. The primary report's outcome was time to failure by 12 months postoperatively, defined by a composite outcome of objective prolapse of the anterior or posterior walls beyond the hymen or the vaginal apex descending below one-third the total vaginal length, subjective bulge symptoms, and/or retreatment. After 12 months, participants could choose to use-or not use-vaginal estrogen for atrophy symptom bother. The secondary outcomes included Pelvic Organ Prolapse Quantification points, subjective prolapse symptom severity using the Patient Global Impression of Severity and the Patient Global Impression of Improvement, and prolapse-specific subscales of the 20-Item Pelvic Floor Distress Inventory and the Pelvic Floor Impact Questionnaire-Short Form 7. Data were analyzed as intent to treat and "per protocol" (ie, ≥50% of expected cream use per medication diary).

RESULTS

Of 206 postmenopausal patients, 199 were randomized, and 186 underwent surgery. Moreover, 164 postmenopausal patients (88.2%) provided 36-month data. The mean age was 65.0 years (standard deviation, 6.7). The characteristics were similar at baseline between the groups. Composite surgical failure rates were not significantly different between the estrogen group and the placebo group through 36 months, with model-estimated failure rates of 32.6% (95% confidence interval, 21.6%-42.0%) and 26.8% (95% confidence interval, 15.8%-36.3%), respectively (adjusted hazard ratio, 1.55; 95% confidence interval, 0.90-2.66; P=.11). The results were similar for the per-protocol analysis. Objective failures were more common than subjective failures, combined objective and subjective failures, or retreatment. Using the Patient Global Impression of Improvement, 75 of 80 estrogen participants (94%) and 72 of 76 placebo participants (95%) providing 36-month data reported that they were much or very much better 36 months after surgery (P>.99). These data included reports from 51 of 55 "surgical failures." Pelvic Organ Prolapse Quantification measurements, Patient Global Impression of Severity scores, and prolapse subscale scores of the 20-Item Pelvic Floor Distress Inventory and Pelvic Floor Impact Questionnaire-Short Form 7 all significantly improved for both the estrogen and placebo groups from baseline to 36 months postoperatively without differences between the groups. Of the 160 participants providing data on vaginal estrogen usage at 36 months postoperatively, 40 of 82 participants (49%) originally assigned to the estrogen group were using prescribed vaginal estrogen, and 47 of 78 participants (60%) assigned to the placebo group were using vaginal estrogen (P=.15).

CONCLUSION

Adjunctive perioperative vaginal estrogen applied ≥5 weeks preoperatively and 12 months postoperatively did not improve surgical success rates 36 months after uterosacral or sacrospinous ligament suspension prolapse repair. Patient perception of improvement remained very high at 36 months.

Perioperative Vaginal Estrogen as Adjunct to Native Tissue Vaginal Apical Prolapse Repair: A Randomized Clinical Trial

Importance

Surgical repairs of apical/uterovaginal prolapse are commonly performed using native tissue pelvic ligaments as the point of attachment for the vaginal cuff after a hysterectomy. Clinicians may recommend vaginal estrogen in an effort to reduce prolapse recurrence, but the effects of intravaginal estrogen on surgical prolapse management are uncertain.

Objective

To compare the efficacy of perioperative vaginal estrogen vs placebo cream on prolapse recurrence following native tissue surgical prolapse repair.

Design, Setting, and Participants

This randomized superiority clinical trial was conducted at 3 tertiary US clinical sites (Texas, Alabama, Rhode Island). Postmenopausal women (N = 206) with bothersome anterior and apical vaginal prolapse interested in surgical repair were enrolled in urogynecology clinics between December 2016 and February 2020.

Interventions

The intervention was 1 g of conjugated estrogen cream (0.625 mg/g) or placebo, inserted vaginally nightly for 2 weeks and then twice weekly to complete at least 5 weeks of application preoperatively; this continued twice weekly for 12 months postoperatively. Participants underwent a vaginal hysterectomy (if uterus present) and standardized apical fixation (either uterosacral or sacrospinous ligament fixation).

Main Outcomes and Measures

The primary outcome was time to failure of prolapse repair by 12 months after surgery defined by at least 1 of the following 3 outcomes: anatomical/objective prolapse of the anterior or posterior walls beyond the hymen or the apex descending more than one-third of the vaginal length, subjective vaginal bulge symptoms, or repeated prolapse treatment. Secondary outcomes included measures of urinary and sexual function, symptoms and signs of urogenital atrophy, and adverse events.

Results

Of 206 postmenopausal women, 199 were randomized and 186 underwent surgery. The mean (SD) age of participants was 65 (6.7) years. The primary outcome was not significantly different for women receiving vaginal estrogen vs placebo through 12 months: 12-month failure incidence of 19% (n = 20) for vaginal estrogen vs 9% (n = 10) for placebo (adjusted hazard ratio, 1.97 [95% CI, 0.92-4.22]), with the anatomic recurrence component being most common, rather than vaginal bulge symptoms or prolapse repeated treatment. Masked surgeon assessment of vaginal tissue quality and estrogenization was significantly better in the vaginal estrogen group at the time of the operation. In the subset of participants with at least moderately bothersome vaginal atrophy symptoms at baseline (n = 109), the vaginal atrophy score for most bothersome symptom was significantly better at 12 months with vaginal estrogen.

Conclusions and Relevance

Adjunctive perioperative vaginal estrogen application did not improve surgical success rates after native tissue transvaginal prolapse repair.

Trial Registration

ClinicalTrials.gov Identifier: NCT02431897.

Evidence for Menopause as a Sex-Specific Risk Factor for Glaucoma

Glaucoma is a leading cause of irreversible blindness worldwide and is characterized by progressive loss of visual function and retinal ganglion cells (RGC). Current epidemiological, clinical, and basic science evidence suggest that estrogen plays a role in the aging of the optic nerve. Menopause, a major biological life event affecting all women, coincides with a decrease in circulating sex hormones, such as estrogen. While 59% of the glaucomatous population are females, sex is not considered a risk factor for developing glaucoma. In this review, we explore whether menopause is a sex-specific risk factor for glaucoma. First, we investigate how menopause is defined as a sex-specific risk factor for other pathologies, including cardiovascular disease, osteoarthritis, and bone health. Next, we discuss clinical evidence that highlights the potential role of menopause in glaucoma. We also highlight preclinical studies that demonstrate larger vision and RGC loss following surgical menopause and how estrogen is protective in models of RGC injury. Lastly, we explore how surgical menopause and estrogen signaling are related to risk factors associated with developing glaucoma (e.g., intraocular pressure, aqueous outflow resistance, and ocular biomechanics). We hypothesize that menopause potentially sets the stage to develop glaucoma and therefore is a sex-specific risk factor for this disease.

Design of a Randomized Clinical Trial of Perioperative Vaginal Estrogen Versus Placebo With Transvaginal Native Tissue Apical Prolapse Repair (Investigation to Minimize Prolapse Recurrence of the Vagina using Estrogen: IMPROVE)

OBJECTIVES

To provide the rationale and design for a randomized, double-blind clinical trial of conjugated estrogen vaginal cream (applied for at least 5 weeks preoperatively and continued twice-weekly through 12 months postoperatively) compared with placebo in postmenopausal women with symptomatic pelvic organ prolapse undergoing a standardized transvaginal native tissue apical repair.

METHODS

Study population, randomization process, study cream intervention, masking of participants and evaluators, placebo cream manufacture, standardized surgical intervention, and collection of adverse events are described. The primary outcome of surgical success is a composite of objectively no prolapse beyond the hymen and the vaginal cuff descending no more than one third the vaginal length; subjectively, no sense of vaginal pressure or bulging; and no retreatment for prolapse at 12 months. Time-to-failure postoperatively will be compared in the 2 groups with continued surveillance to 36 months. Secondary outcomes assessed at baseline, preoperatively (ie, after at least 5 weeks of study cream), and postoperatively at 6 month intervals include validated condition-specific and general quality-of-life metrics, overall impression of improvement, sexual function, vaginal atrophy symptoms, and body image. Challenges unique to this study include design and manufacture of placebo and defining and measuring study drug adherence.

RESULTS

Recruitment of 204 women is complete with 197 randomized. There have been 174 surgeries completed with 15 more pending; 111 have completed their 12 month postoperative visit.

CONCLUSIONS

This trial will contribute evidence-based information regarding the effect of perioperative vaginal estrogen as an adjunct therapy to standardized transvaginal native tissue prolapse surgical repair.

Risk factors for vaginal mesh erosion after sacrocolpopexy in Korean women

Objective

Although sacrocolpopexy (SCP) can provide durable apical support, the use of mesh may give rise to various complications, including vaginal mesh erosion. The aim of this study was to identify the risk factors for vaginal mesh erosion after SCP in Korean women.

Methods

This retrospective cohort study included 363 women who underwent SCP with type 1 polypropylene mesh. They were evaluated at 1, 4, and 12 months after surgery and then annually thereafter with respect to anatomy and complications. Univariate and multivariate analyses using the Cox proportional hazard model were performed to identify the risk factors for mesh erosion.

Results

During the median 2-year follow-up period, vaginal mesh erosion was found in 29 women (8.0%). Among them, 19 (65.5%) required surgical correction. Estrogenic status was the only independent risk factor for mesh erosion. The risk for mesh erosion was 4.5 times higher in premenopausal women than in menopausal women not on estrogen replacement therapy (ERT) (95% confidence intervals [CI] 1.9–10.9, p<0.01). Menopausal women on ERT also had an increased risk, with a statistically marginal significance (hazard ratio 2.5, 95% CI 0.9–6.6; p = 0.07).

Conclusions

Premenopausal or menopausal women on ERT are at high risk for mesh erosion after SCP with type 1 polypropylene mesh, and two-thirds of mesh erosion cases require reoperation. This information should be incorporated into patient counseling and treatment decisions.

Estrogen receptor and laminin genetic polymorphism among women with pelvic organ prolapse

OBJECTIVE

Laminin is a connective tissue component. The LAMC1 gene encodes for gamma-1 chain of laminin, which is associated with familial clustering of POP. The ERα gene which encodes for cellular estrogen receptor has also been associated with POP. The aim of this study was to evaluate a possible correlation between polymorphism in these genes and the risk for developing POP.

MATERIALS AND METHODS

Blood samples were drawn from 33 women with advanced POP (study group) and 33 women without POP (control group). DNA was extracted, and the presence of the rs10911193 C/T mutation in LAMC1 and of the rs2228480 G/A mutation in ERα was detected using the PCR technique.

RESULTS

26 samples were available for each group regarding ERα. 33 samples were available for each group, regarding LAMC1. The prevalence of homozygotes for the ERα rs2228480 G/A mutation was 19.2% and 0% among women with and without POP, respectively (OR 39.77, 95% CI 1.93-817.0, P = 0.00046). The prevalence of heterozygotes for this mutation was 83.3% and 11.5%, respectively (OR 19.2, 95% CI 4.15-88.6, P < 0.0001). The prevalence of homozygotes for the LAMC1 gene rs10911193 C/T mutation was 3.6% and 6.1% among women with and without POP (NS), while the respective for heterozygotes for this mutation was 21.4% and 33.3% (NS).

CONCLUSIONS

Polymorphism in the ERα gene is associated with an increased risk for advanced POP. However, polymorphism in the LAMC1 gene does not seem to be associated with such risk.

Pelvic Organ Support in Animals with Partial Loss of Fibulin-5 in the Vaginal Wall

Compromise of elastic fiber integrity in connective tissues of the pelvic floor is most likely acquired through aging, childbirth-associated injury, and genetic susceptibility. Mouse models of pelvic organ prolapse demonstrate systemic deficiencies in proteins that affect elastogenesis. Prolapse, however, does not occur until several months after birth and is thereby acquired with age or after parturition. To determine the impact of compromised levels of fibulin-5 (Fbln5) during adulthood on pelvic organ support after parturition and elastase-induced injury, tissue-specific conditional knockout (cKO) mice were generated in which doxycycline (dox) treatment results in deletion of Fbln5 in cells that utilize the smooth muscle α actin promoter-driven reverse tetracycline transactivator and tetracycline responsive element-Cre recombinase (i.e., Fbln5f/f/SMA++-rtTA/Cre+, cKO). Fbln5 was decreased significantly in the vagina of cKO mice compared with dox-treated wild type or controls (Fbln5f/f/SMA++-rtTA/Cre-/-). In controls, perineal body length (PBL) and bulge increased significantly after delivery but declined to baseline values within 6-8 weeks. Although overt prolapse did not occur in cKO animals, these transient increases in PBL postpartum were amplified and, unlike controls, parturition-induced increases in PBL (and bulge) did not recover to baseline but remained significantly increased for 12 wks. This lack of recovery from parturition was associated with increased MMP-9 and nondetectable levels of Fbln5 in the postpartum vagina. This predisposition to prolapse was accentuated by injection of elastase into the vaginal wall in which overt prolapse occurred in cKO animals, but rarely in controls. Taken together, our model system in which Fbln5 is conditionally knock-downed in stromal cells of the pelvic floor results in animals that undergo normal elastogenesis during development but lose Fbln5 as adults. The results indicate that vaginal fibulin-5 during development is crucial for baseline pelvic organ support and is also important for protection and recovery from parturition- and elastase-induced prolapse.

Collagen metabolic disorder induced by oxidative stress in human uterosacral ligament‑derived fibroblasts: A possible pathophysiological mechanism in pelvic organ prolapse

Pelvic organ prolapse (POP) is a global health problem, for which the pathophysiological mechanism remains to be fully elucidated. The loss of extracellular matrix protein has been considered to be the most important molecular basis facilitating the development of POP. Oxidative stress (OS) is a well-recognized mechanism involved in fiber metabolic disorders. The present study aimed to clarify whether OS exists in the uterosacral ligament (USL) with POP, and to investigate the precise role of OS in collagen metabolism in human USL fibroblasts (hUSLFs). In the present study, 8-hydroxyguanosine (8-OHdG) and 4 hydroxynonenal (4-HNE), as oxidative biomarkers, were examined by immunohistochemistry to evaluate oxidative injury in USL sections in POP (n=20) and non-POP (n=20) groups. The primary cultured hUSLFs were treated with exogenous H₂O₂ to establish an original OS cell model, in which the expression levels of collagen, type 1, α1 (COL1A1), matrix metalloproteinase (MMP)-2, tissue inhibitor of metalloproteinase (TIMP)-2 and transforming growth factor (TGF)-β1 were evaluated by western blot and reverse transcription-quantitative polymerase chain reaction analyses. The results showed that the expression levels of 8-OHdG and 4-HNE in the POP group were significantly higher, compared with those in the control group. Collagen metabolism was regulated by H₂O₂ exposure in a concentration-dependent manner, in which lower concentrations of H₂O₂ (0.1–0.2 mM) stimulated the anabolism of COL1A1, whereas a higher concentration (0.4 mM) promoted catabolism. The expression levels of MMP-2, TIMP-2 and TGF-β1 exhibited corresponding changes with the OS levels. These results suggested that OS may be involved in the pathophysiology of POP by contributing to collagen metabolic disorder in a severity-dependent manner in hUSLFs, possibly through the regulation of MMPs, TIMPs and TGF-β1 indirectly.

MicroRNA-30d and microRNA-181a regulate HOXA11 expression in the uterosacral ligaments and are overexpressed in pelvic organ prolapse

The balanced turnover of collagen is necessary to maintain the mechanical strength of pelvic supportive connective tissues. Homeobox (HOX) A11 is a key transcriptional factor that controls collagen metabolism and homoeostasis in the uterosacral ligaments (USLs), and the deficient HOXA11 signalling may contribute to alterations in the biochemical strength of the USLs, leading to pelvic organ prolapse (POP). However, it is unknown how HOXA11 transcripts are regulated in the USLs. In this study, we found that microRNA (miRNA)-30d and 181a were overexpressed in women with POP, and their expression was inversely correlated with HOXA11 mRNA levels. The overexpression of miR-30d or 181a suppressed HOXA11 mRNA and protein levels in 293T cells, whereas the knockdown of these miRNAs enhanced HOXA11 levels and collagen production. Cotransfection of a luciferase reporter plasmid containing the 3′-untranslated region of HOXA11 with miR-30d or 181a mimic resulted in decreased relative luciferase activity. Conversely, cotransfection with anti-miR-30d or 181a increased luciferase activity. Taken together, these results indicate that both miR-30d and 181a are important posttranscriptional regulators of HOXA11 in the USLs and could be a potential therapeutic target for POP.

The effect of ascorbic acid and fluid flow stimulation on the mechanical properties of a tissue engineered pelvic floor repair material

Synthetic non-degradable meshes used in pelvic floor surgery can cause serious complications such as tissue erosion. A repair material composed of an autologous oral fibroblast seeded degradable polylactic acid scaffold may be a viable alternative. The aims of this study were to investigate the effects of media supplementation with additives (ascorbic acid-2-phosphate, glycolic acid and 17-β-oestradiol) on the mechanical properties of these scaffolds. Oral fibroblasts were isolated from buccal mucosa. The effects of the three additives were initially compared in two-dimensional culture to select the most promising collagen stimulating additive. Sterile electrospun scaffolds were seeded with 500,000 oral fibroblasts and fixed in 6-well plates and subjected to ascorbic acid-2-phosphate (the best performing additive) and/or mechanical stimulation. Mechanical stimulation by fluid shear stress was induced by rocking scaffolds on a platform shaker for 1 h/day for 10 of 14 days of culture. In two-dimensional culture, ascorbic acid-2-phosphate (concentrations from 0.02 mM to 0.04 M) and glycolic acid (10 µM) led to significantly greater total collagen production, but ascorbic acid-2-phosphate at 0.03 mM produced the greatest stimulation (of the order of >100%). In three-dimensional culture, mechanical stimulation alone gave non-significant increases in stiffness and strength. Ascorbic acid-2-phosphate (0.03 mM) significantly increased collagen production in the order 280% in both static and mechanically stimulated scaffolds (p < 0.0001). There was no additional effect of mechanical stimulation. Dense collagen I fibres were observed with ascorbic acid-2-phosphate supplementation. Uniaxial tensiometry showed that strength (p < 0.01) and stiffness (p <0.05) both improved significantly. A combination of ascorbic acid-2-phosphate and mechanical stimulation led to further non-signficant increases in strength and stiffness. In conclusion, a pelvic floor repair material with improved mechanical properties can be developed by supplementing culture media with ascorbic acid-2-phosphate to increase collagen I production. Future studies will assess the change in mechanical properties after implantation in an animal model.

Impact of oral contraceptive use and menstrual phases on patellar tendon morphology, biochemical composition, and biomechanical properties in female athletes

Sex differences exist with regards to ligament and tendon injuries. Lower collagen synthesis has been observed in exercising women vs. men, and in users of oral contraceptives (OC) vs. nonusers, but it is unknown if OC will influence tendon biomechanics of women undergoing regular training. Thirty female athletes (handball players, 18-30 yr) were recruited: 15 long-term users of OC (7.0 ± 0.6 yr) and 15 nonusers (>5 yr). Synchronized values of patellar tendon elongation (obtained by ultrasonography) and tendon force were sampled during ramped isometric knee extensor maximum voluntary contraction to estimate mechanical tendon properties. Furthermore, tendon cross-sectional area and length were measured from MRI images, and tendon biopsies were obtained for analysis of tendon fibril characteristics and collagen cross-linking. Overall, no difference in tendon biomechanical properties, tendon fibril characteristics, or collagen cross-linking was observed between the OC users and nonusers, or between the different phases of the menstrual cycle. In athletes, tendon cross-sectional area in the preferred jumping leg tended to be larger than that in the contralateral leg (P = 0.09), and a greater absolute (P = 0.01) and normalized tendon stiffness (P = 0.02), as well as a lower strain (P = 0.04), were observed in the jumping leg compared with the contralateral leg. The results indicate that long-term OC use or menstrual phases does not influence structure or mechanical properties of the patellar tendon in female team handball athletes.

Alterations in connective tissue metabolism in stress incontinence and prolapse

PURPOSE

We describe current knowledge about collagen/elastin and extracellular matrix metabolism in the genitourinary tract with special emphasis on stress urinary incontinence. We also explored the influence of genetics and reproductive hormones on extracellular matrix metabolism.

MATERIALS AND METHODS

We performed a MEDLINE® search from 1995 to February 2011 using the key words stress urinary incontinence, pelvic organ prolapse, extracellular matrix, collagen, elastin, matrix metalloproteinase, collagenase, tissue inhibitors of matrix metalloproteinase, elastin metabolism, elastase, connective tissue, supportive tissue, mechanical stress, biomechanical properties, selective estrogen receptor modulators, transforming growth factor-β and wound healing.

RESULTS

The literature searched produced data on 4 areas of significance for extracellular matrix metabolism in patients with stress urinary incontinence and prolapse, including collagen, elastin and transforming growth factor-β. Data on collagen metabolism continue to support the hypothesis of increased turnover involving matrix metalloproteinases and serine proteases in pelvic tissues of affected individuals. Elastin metabolism studies suggest increased degradation but also abnormal elastin fiber synthesis. Epidemiological data indicate a genetic predisposition to abnormal extracellular matrix in affected individuals while human tissue and animal models reveal differential expression of candidate genes involved in structural proteins. Transforming growth factor-β pathways have been documented to be involved in stress urinary incontinence in human tissues and animal models. Finally, these extracellular matrix metabolisms are modulated by reproductive hormones and selective estrogen receptor modulators.

CONCLUSIONS

Pelvic tissue from women with stress urinary incontinence and pelvic organ prolapse show a genetic predisposition to abnormal extracellular matrix remodeling, which is modulated by reproductive hormones, trauma, mechanical stress load and aging. This progressive remodeling contributes to stress urinary incontinence/pelvic organ prolapse by altering normal tissue architecture and mechanical properties.

Repetitive mechanical stretch increases extracellular collagenase activity in vaginal fibroblasts

OBJECTIVES: The objectives were 1) to determine whether human vaginal fibroblasts are mechanosensitive and 2) to study the impact of mechanical stretch on these cells in the presence and absence of hormones. METHODS: Fibroblasts obtained from biopsies of full thickness vagina of 3 women were cyclically biaxially stretched at a magnitude of 8 and 16% for 72 hours with or without 17-β-estradiol plus progesterone. Culture media was collected and total collagenase activity was measured in duplicate using a fluorogenic substrate degradation assay. Data were analyzed at the 0.05 level of significance using Student t-test. RESULTS: Cells remained 90% viable throughout the experiments. Relative to the controls, hormonal treatment alone decreased collagenase activity (P=0.008). In the presence of mechanical stretch and in the absence of hormones, collagenase activity was increased (8% elongation, P=0.04; 16% elongation, P=0.001, respectively). The increase in collagenase activity was linearly correlated with magnitude (P<0.001). In the presence of hormones, the increase in enzyme activity by mechanical stretch was suppressed to baseline control levels (P=0.46). There was no difference in suppression by hormones by magnitude (P=0.48). CONCLUSIONS: Vaginal connective tissue fibroblasts are mechanosensitive with increased collagenase activity in the presence of stretch. This degradative behavior is inhibited in the presence of hormones. The data provide a mechanism by which events that induce vaginal stretch may lead to progression of pelvic organ prolapse, particularly, in the absence of hormones. Further studies are needed to determine whether these events lead to tissue with inferior mechanical properties.

17beta-Estradiol inhibits matrix metalloproteinase-2 transcription via MAP kinase in fibroblasts

AIMS

Female sex and sex hormones contribute to cardiac remodelling. 17beta-estradiol (E2) is involved in the modulation of extracellular matrix composition and function. Here, we analysed the effect of E2 on matrix metalloproteinase (MMP)-2 gene expression and studied the underlying molecular mechanisms in rat cardiac fibroblasts and in a human fibroblast cell line.

METHODS AND RESULTS

In adult rat cardiac fibroblasts, E2 significantly decreased MMP-2 gene expression in an estrogen receptor (ER)-dependent manner. Transient transfection experiments of human MMP-2 (hMMP-2) promoter deletion constructs in a human fibroblast cell line revealed a regulatory region between -324 and -260 bp that is involved in E2/ERalpha-mediated repression of hMMP-2 gene transcription. Electrophoretic mobility shift assays (EMSA) and supershift analysis demonstrated the binding of transcription factor Elk-1 within this promoter region. Elk-1 was phosphorylated by E2 via the mitogen-activated protein kinase (MAPK) signalling pathway as shown by western blotting. Treatment of cells with the MAPK inhibitor PD98059 blocked the E2-dependent repression of hMMP-2 promoter activity as well as the endogenous MMP-2 mRNA levels in both human fibroblast cells and rat cardiac fibroblasts.

CONCLUSION

E2 inhibits MMP-2 expression via the ER and the MAPK pathway in rat cardiac fibroblasts and in a human fibroblast cell line. These mechanisms may contribute to sex-specific differences in fibrotic processes that are observed in human heart and other diseases.

Matrix metalloproteinases-1, -2 expression in uterosacral ligaments from women with pelvic organ prolapse

OBJECTIVE

This study investigated matrix metalloproteinase-1 (MMP-1) and matrix metalloproteinase-2 (MMP-2) immunohistochemical expression in uterosacral ligament biopsies from women with pelvic organ prolapse (POP), and controls with normal pelvic support.

DESIGN

Prospective observational experimental study.

SETTING

A tertiary Urogynecology Unit and Institute of Pathology, University Hospital Split, Croatia.

POPULATION

Women referred for hysterectomy for prolapse or benign gynecological disease.

METHODS

Eighty postmenopausal women were included in the study after Ethical Committee approval and informed consent. During surgery, uterosacral ligament biopsies were obtained from patients with POP (n=40) and women without evidence of pelvic floor weakening (n=40). Immunohistochemistry for MMP-1 and MMP-2 was performed on formaline fixed and paraffin embedded sections. Statistical evaluations were made by Student t-test or chi(2) test.

MAIN OUTCOME MEASURES

Immunohistochemical expression of MMP-1 and MMP-2 in the uterosacral ligaments of women with and without genital prolapse.

RESULTS

Forty women with POP and 40 controls without POP were included. The controls were matched to the women with POP in age, body mass index, parity and duration of postmenopausis. A significant increase in MMP-1 immunohistochemical expression was seen in uterosacral ligament tissue from women with POP (P=0.029). In contrast, there was no difference in immunohistochemical expression of MMP-2 between women with POP and those without (P=0.899).

CONCLUSION

These data suggest that MMP-1 may be marker of collagen degradation. Increased MMP-1 immunohistochemical expression in uterosacral ligaments is associated with urogenital prolapse.

The amount and activity of active matrix metalloproteinase 13 is suppressed by estradiol and progesterone in human pelvic floor fibroblasts

As a key degrader of fibrillar collagens, matrix metalloproteinase 13 (MMP13), may contribute to the progression of pelvic organ prolapse. Here we aimed to define the regulation of MMP13 by estradiol and progesterone in the vaginal supportive tissues. Fibroblasts cultured from the arcus tendineous fasciae pelvis of three pre- and three postmenopausal women with prolapse were treated with 17-beta-estradiol (E2), progesterone (P4), E2 + P4, or E2 + ICI 182,780 (ICI). Collagenase inhibitor I (CI) and MG-132 were employed to investigate the mechanism of MMP13 degradation into inactive fragments (fragmentation) by hormones. The regulation of MMP13 in vivo was assessed by comparing tissues of ovariectomized (ovx) vs. sham-operated rats. Expression of MMP13 (proenzyme and active and fragment forms) was quantitated by Western immunoblotting, and MMP13 enzymatic activity was measured using a substrate degradation assay. The amount of cellular active MMP13 and MMP13 proteolytic activity decreased in the presence of hormones. The decrease was paralleled by increased proenzyme and fragment forms. MG-132, not CI, suppressed cellular MMP13 fragmentation. Active MMP13 increased in rats following ovx and was suppressed by E2 + P4 supplementation. Active MMP13 is suppressed in vivo and in vitro by estradiol and progesterone, suggesting a protective effect against vaginal supportive tissue deterioration.

Hormones restore biomechanical properties of the vagina and supportive tissues after surgical menopause in young rats

OBJECTIVE

The objective of the study was to determine the impact of hormones on the biomechanical properties of the vagina and its supportive tissues following surgical menopause in young vs middle-aged rats.

STUDY DESIGN

Long-Evans rats (4-month virgin [n = 34], 4-month parous [n = 36], and 9-month parous [n = 34]), underwent ovariectomy (OVX) or sham surgery. OVX animals received hormones (estrogen [E2] or estrogen plus progesterone [E2 plus P4]), placebo, or a matrix metalloproteinase inhibitor (chemically modified tetracycline-8 [CMT-8]). Animals were euthanized after 8 weeks and the biomechanical properties of the vagina and supportive tissues determined. Data were analyzed using a 1-way analysis of variance and posthoc tests.

RESULTS

OVX induced a rapid decline in the biomechanical properties of pelvic tissues in young but not middle-aged rats. Supplementation with E2, E2 plus P4, or CMT-8 restored tissues of young rats to control levels with no effect on middle-aged tissues. Parity did not have an impact on tissue behavior.

CONCLUSION

OVX has a differential effect on the tissues of young vs middle-aged rats.

Effect of vaginal distention on elastic fiber synthesis and matrix degradation in the vaginal wall: potential role in the pathogenesis of pelvic organ prolapse

Matrix metalloprotease (MMP) activity is increased in the postpartum vagina of wild-type (WT) animals. This degradative activity is also accompanied by a burst in elastic fiber synthesis and assembly. The mechanisms that precipitate these changes are unclear. The goals of this study were to determine how vaginal distention (such as in parturition) affects elastic fiber homeostasis in the vaginal wall and the potential significance of these changes in the pathogenesis of pelvic organ prolapse. Vaginal distention with a balloon simulating parturition resulted in increased MMP-2 and MMP-9 activity in the vaginal wall of nonpregnant and pregnant animals. This was accompanied by visible fragmented and disrupted elastic fibers in the vaginal wall. In nonpregnant animals, the abundant amounts of tropoelastin and fibulin-5 in the vagina were not increased further by distention. In contrast, in pregnant animals, the suppressed levels of both proteins were increased 3-fold after vaginal distention. Distention performed in fibulin-5-deficient (Fbln5(-/-)) mice with defective elastic fiber synthesis and assembly induced accelerated pelvic organ prolapse, which never recovered. We conclude that, in pregnant mice, vaginal distention results in increased protease activity in the vaginal wall but also increased synthesis of proteins important for elastic fiber assembly. Distention may thereby contribute to the burst of elastic fiber synthesis in the postpartum vagina. The finding that distention results in accelerated pelvic organ prolapse in Fbln5(-/-) animals, but not in WT, indicates that elastic fiber synthesis is crucial for recovery of the vaginal wall from distention-induced increases in vaginal protease activity.

The contractile properties of vaginal myofibroblasts: is the myofibroblasts contraction force test a valuable indication of future prolapse development?

Using a specific myofibroblast contraction test, we try to predict future utero-vaginal prolapse development in young primiparae women. We compare myofibroblast cultures of the vaginal wall in primiparae women (group 1), young multiparae women (group 2) and older multiparae women (group 3) who were operated on for severe utero-vaginal prolapse. A myofibroblast-mediated collagen gel contraction assay determined a contraction factor that was compared in the three groups of women. The myofibroblasts contraction factor after 24 and 48 hours was significantly higher in group 1 women (2.4 +/- 0.6/4.4 +/- 1.9) compared to group 2 (1.6 +/- 0.3/ 1.8 +/- 0.1) andgroup 3 (1.6 +/- 0.3/1.8 +/- 0.3), but showed no differences in group 1 women without (2.1 +/- 0.5/3.5 +/- 1.9) and with (2.7 +/- 0.6/5.1 +/- 1.7) cystocoele. Vaginal myofibroblasts of young women show better contraction forces than young women with severe utero-vaginal prolapse. The latter have a myofibroblast contraction factor similar to those of older post-menopausal women operated for the same condition.

Cosmetic surgery considerations in the female patient

A greater number of women than men undergo facial cosmetic procedures. Oral and maxillofacial surgeons should have an in-depth knowledge of the physiologic and anatomic differences between the sexes with respect to surgical treatment options. Gender differences in regard to the planning and management of female cosmetic surgery patients are the focus of this article.

Evidence that estrogen receptor beta enhances MMP-13 promoter activity in HIG-82 cells and that this enhancement can be influenced by ligands and involves specific promoter sites

Degradation of articular cartilage is characteristic of osteoarthritis, and matrix metalloproteinase-13 (MMP-13) has been implicated in this condition. Estrogen receptors (ERs) are present in connective tissues, indicating these tissues' potential responsiveness to estrogen. We based this study on the hypothesis that estrogen receptor beta (ERbeta) can modulate MMP-13 promoter activity. Transfection of cells with ERbeta constructs led to the induction of the endogenous MMP-13 gene, as evidenced by increased mRNA levels. The results also indicated that MMP-13 promoter construct activity in the HIG-82 cell line significantly increased when ERbeta was present, and that estrogen downregulated this response in a dose-dependent manner. ERbeta was shown to enhance MMP-13 expression somewhat more strongly than ERalpha, and the impact of a number of selective ER modulators (tamoxifen, raloxifene, and ICI 182,780) on ERbeta enhancement of promoter activity was found to be significantly less than that of estrogen. Furthermore, transcription regulatory sites in the MMP-13 promoter, specifically AP-1 and PEA-3, were shown to act in conjunction to mediate ERbeta effects. Thus, ERbeta likely influences MMP-13 promoter expression in normal and disease processes.

Roles of sex steroid receptors and cell cycle regulation in pathogenesis of pelvic organ prolapse

PURPOSE OF REVIEW

The cause of pelvic organ prolapse is multifactorial and many inciting, promoting and decompensating factors play a role in developing pelvic organ prolapse. Various clinical parameters have been studied quite extensively, but estrogen and collagen metabolism and cell proliferation and apoptosis have not been widely evaluated. This review focuses on assessing the roles of estrogen and its receptor, relationship with collagen metabolism and cell proliferation and cell apoptosis in development and progression of pelvic organ prolapse.

RECENT FINDINGS

Differential expressions of sex steroid receptors in various suspensory ligaments of prolapsed uteri have been studied. How different subtypes of estrogen receptor play a role in inducing and aggravating pelvic organ prolapse has yet to be defined. The role of estrogen in collagen metabolism and cell proliferation related to development of pelvic organ prolapse is still under study. Studies on the proliferation of fibroblasts in ligaments of pelvic organ prolapse have yielded conflicting results.

SUMMARY

There is still a need for additional research on precise roles of sex steroids, their receptors and cell cycle regulatory proteins and cell proliferation in pathogenesis of pelvic organ prolapse. Some of them could be the cause of pelvic organ prolapse and some of them the direct result of tissue trauma in pelvic organ prolapse.

Regulation of MMP-1 by sex steroid hormones in fibroblasts derived from the female pelvic floor

OBJECTIVE

The aim of this study was to investigate the effect of sex steroid hormones on the overall expression profile of cellular matrix metalloproteinase-1 (MMP-1) in fibroblasts that are derived from arcus tendineus fasciae pelvis.

STUDY DESIGN

Arcus tendineus fasciae pelvis fibroblasts that originated from a premenopausal woman and a postmenopausal woman who was undergoing a prolapse repair were treated with physiologic concentrations of 17-beta-estradiol (E2), progesterone, E2 plus progesterone, and E2 plus ICI 182,780. Cellular expressions of the latent, active, and fragment forms of MMP-1 were analyzed quantitatively by Western immunoblotting.

RESULTS

The latent and fragment forms of MMP-1 were increased by E2, progesterone, and E2 plus progesterone. The active form of MMP-1 was not changed by either E2 or progesterone alone but was decreased significantly when both hormones were added together. ICI 182,780 inhibited the stimulatory effect of E2.

CONCLUSION

Fragmentation is a site of regulation of MMP-1 expression by hormones. Only E2 combined with progesterone decreased the active form of MMP-1, which suggests that both hormones are necessary to maintain the integrity of female pelvic floor.

Pelvic organ prolapse in fibulin-5 knockout mice: pregnancy-induced changes in elastic fiber homeostasis in mouse vagina

Pelvic organ prolapse is strongly associated with a history of vaginal delivery. The mechanisms by which pregnancy and parturition lead to failure of pelvic organ support, however, are not known. Recently, it was reported that mice with null mutations in lysyl oxidase-like 1 (LOXL1) develop pelvic organ prolapse. Elastin is a substrate for lysyl oxidase (LOX) and LOXL1, and LOXL1 interacts with fibulin-5 (FBLN5). Therefore, to clarify the potential role of elastic fiber assembly in the pathogenesis of pelvic organ prolapse, pelvic organ support was characterized in Fbln5-/- mice, and changes in elastic fiber homeostasis in the mouse vagina during pregnancy and parturition were determined. Pelvic organ prolapse in Fbln5-/- mice was remarkably similar to that in primates. The temporal relationship between LOX mRNA and protein, processing of LOXL1 protein, FBLN5 and tropoelastin protein, and desmosine content in the vagina suggest that a burst of elastic fiber assembly and cross linking occurs in the vaginal wall postpartum. Together with the phenotype of Fbln5-/- mice, the results suggest that synthesis and assembly of elastic fibers are crucial for recovery of pelvic organ support after vaginal delivery and that disordered elastic fiber homeostasis is a primary event in the pathogenesis of pelvic organ prolapse in mice.

Effect of 17beta-estradiol on apoptosis, IGF system components and gelatinases A and B in prostate cancer cells (PC-3)

BACKGROUND

Previous studies have indicated that estrogen administration in the advanced stage of prostate cancer provide some benefits to the patients. Estrogen action was thought to be mediated via the blockade of the pituitary-testicular axis that effectively lowered the circulating levels of androgen and, thus, results in tumor regression; however, the effect of estrogens on prostate epithelial cells is still unclear. We investigated the effects of estradiol on insulin-like growth factor type I receptor (IGF-IR), IGF-binding protein 3 (IGFBP-3), IGFBP-4, and matrix metalloproteinase 2 (MMP-2) and MMP-9 in androgen-independent prostate cancer cells (PC-3).

METHODS

The cells were treated with different concentrations of estradiol (1, 10 and 100 nmol/l) for different time periods (24, 48, 72 and 96 h). Cell proliferation was assessed using MTT assay, and IGFBP-3 and IGFBP-4 were assessed using immunoradiometric and enzyme immunoassays, respectively. MMP-2, MMP-9 and IGF-IR expression levels were analyzed using western-blot analysis, and MMP-2 and MMP-9 activities were analyzed using gelatin zymography. Apoptosis was confirmed by Annexin V-FITC and acridine orange and ethidium bromide staining methods. DNA fragmentation studies were also performed.

RESULTS

Cell proliferation assay revealed that 10 and 100 nmol/l estradiol concentrations inhibit the proliferation of PC-3 cells when incubated for 48-96 h. The secretory levels of IGFBP-3 and IGFBP-4 were increased significantly. The western-blot results showed that estradiol is capable of decreasing the expression of MMP-2 and MMP-9 significantly. Gelatin zymography showed that activities of MMP-2 and MMP-9 are decreased in estradiol-treated cells. Estradiol-induced apoptosis was studied using annexin V-binding and propidium iodide influx. Estradiol also induced nuclear fragmentation in higher doses (100 nmol/l) in PC-3 cells.

CONCLUSION

Inhibition of MMPs in cancer cells and increased levels of IGFBP-3 and IGFBP-4 associated with apoptosis may be one of the targets for anticancer function of estradiol. Estradiol inhibits the proliferation of prostate cancer cells by inducing apoptosis.

Hernia fibroblasts lack beta-estradiol-induced alterations of collagen gene expression

BACKGROUND

Estrogens are reported to increase type I and type III collagen deposition and to regulate Metalloproteinase 2 (MMP-2) expression. These proteins are reported to be dysregulated in incisional hernia formation resulting in a significantly decreased type I to III ratio. We aimed to evaluate the beta-estradiol mediated regulation of type I and type III collagen genes as well as MMP-2 gene expression in fibroblasts derived from patients with or without history of recurrent incisional hernia disease. We compared primary fibroblast cultures from male/female subjects without/without incisional hernia disease.

RESULTS

Incisional hernia fibroblasts (IHFs) revealed a decreased type I/III collagen mRNA ratio. Whereas fibroblasts from healthy female donors responded to beta-estradiol, type I and type III gene transcription is not affected in fibroblasts from males or affected females. Furthermore beta-estradiol had no influence on the impaired type I to III collagen ratio in fibroblasts from recurrent hernia patients.

CONCLUSION

Our results suggest that beta-estradiol does not restore the imbaired balance of type I/III collagen in incisional hernia fibroblasts. Furthermore, the individual was identified as an independent factor for the beta-estradiol induced alterations of collagen gene expression. The observation of gender specific beta-estradiol-dependent changes of collagen gene expression in vitro is of significance for future studies of cellular response.

The natural history of overactive bladder and stress urinary incontinence in older women in the community: A 3-year prospective cohort study

AIMS

This is the first study designed to describe the natural history of stress urinary incontinence (SUI) and overactive bladder (OAB), using validated symptom syndrome severity scores developed for the purpose.

METHODS

Two separate but related studies were involved, (i) a clinic sample (N = 2,052) from a randomised controlled trial (RCT) and (ii) a prospective cohort study (N = 12,750) with 3-year follow-up. Subjects in both studies were women aged 40 or more living in the community, approached using similar postal questionnaires. Severity scores using standardised urinary symptoms were derived for SUI and OAB from weightings obtained from logistic regression models of symptoms in relation to urodynamic diagnosis. Symptom severity scores were plotted for baseline and 3 years of follow-up to demonstrate the natural history of the main categories of SUI and OAB.

RESULTS

Overactive bladder and SUI syndrome severity scores showed good criterion validity in relation to relevant clinical measures and good test-retest reliability. OAB severity increased progressively with age including a period of accelerated increase in the 60s. In contrast, SUI severity showed two age-related peaks around age 60 and again at age 80. SUI severity also showed a more fluctuating pattern from year to year compared to OAB.

CONCLUSIONS

Contrasting patterns of natural history for OAB and SUI syndromes were identified consistent with differences in the patterns of related co-morbidities. Further studies are needed to confirm these findings.

Role of estrogen deficiency in the formation and progression of cerebral aneurysms. Part I: experimental study of the effect of oophorectomy in rats

Object. Estrogen has been shown to play a central role in vascular biology. Although it may exert beneficial vascular effects, its role in the pathogenesis of cerebral aneurysms remains to be determined. To elucidate the role of hormones further, the authors examined the effects of bilateral oophorectomy on the formation and progression of cerebral aneurysms in rats.

Methods. Forty-five female, 7-week-old Sprague—Dawley rats were divided into three equal groups. Group I consisted of intact rats (controls). To induce cerebral aneurysms, the animals in Groups II and III were subjected to ligation of the right common carotid and bilateral posterior renal arteries. One month later, the rats in Group II underwent bilateral oophorectomy. Three months after the experiment began all animals were killed and cerebral vascular corrosion casts were prepared and screened for cerebral aneurysms by using a scanning electron microscope. Plasma was used to determine the level of estradiol and the gelatinase activity.

Hypertension developed in all rats except those in the control group. The estradiol level was significantly lower in Group II than in the other groups (p < 0.01). The incidence of cerebral aneurysm formation in Group II (60%) was three times higher than that in Group III (20%), and the mean size of aneurysms in Group II (76 ± 27 µm, mean ± standard deviation) was larger than that in Group III (28 ± 4.6 µm) (p < 0.05). No aneurysm developed in control animals (Group I), and there was no significant difference in plasma gelatinase activity among the three groups.

Conclusions. The cerebral aneurysm model was highly reproducible in rats. Bilateral oophorectomy increased the susceptibility of rats to aneurysm formation, indicating that hormones play a role in the pathogenesis of cerebral aneurysms.

Effects of 17beta-estradiol on matrix metalloproteinase-1 synthesis by human dermal fibroblasts

BACKGROUND

Hormone replacement therapy (HRT) has been used in treatment of various menopausal disorders. It has been well documented that HRT increases the amount of dermal collagen and skin thickness in vivo. However little is known about the effects of female sex hormones on dermal fibroblasts in vitro.

OBJECTIVE

The aim of this study is to determine whether or not 17beta-estradiol affects mRNA expression and production of type I collagen, matrix metalloproteinases-1 (MMP-1), tissue inhibitor metalloproteinases-1 (TIMP-1) or transforming growth factor-beta1 (TGF-beta1) by human dermal fibroblasts.

METHODS

Fibroblasts were cultured with and without 17beta-estradiol for 6h. We evaluated the changes of mRNA expressions and protein production of type I collagen, MMP-1, TIMP-1 and TGF-beta1.

RESULTS

The mRNA expressions of collagen alpha1(I), MMP-1, TIMP-1, TGF-beta1 were not changed by 17beta-estradiol stimulations at a concentration of 10(-12) to 10(-8) M. However, 17beta-estradiol at concentrations of 10(-12) and 10(-10) M exhibited inhibitory effects on proMMP-1, but not type I collagen or TIMP-1 synthesis. The synthesis of TGF-beta1 by fibroblasts stimulated with 10(-8) M of estradiol was significantly increased as compared with the control. However, the level of TGF-beta type II receptor phosphorylation was not elevated under the same conditions.

CONCLUSION

Suppressed synthesis of MMP-1 at a low concentration of 17beta-estradiol may be partly involved in the dermal tissue remodeling to inhibit the degradative change.

Estrogen and skin: The effects of estrogen, menopause, and hormone replacement therapy on the skin

Aging is associated with declining levels of several hormones, including estrogen. Although the effects of estrogen on the skin are still not fully understood, it is known that, in women, declining estrogen levels are associated with a variety of cutaneous changes, many of which can be reversed or improved by estrogen supplementation. Estrogens are C-18 steroids synthesized from cholesterol in the ovary premenopausally and in the peripheral tissue in postmenopausal women. Two estrogen receptors, alpha and beta, have been cloned and found in various tissue types. Studies of postmenopausal women indicate that estrogen deprivation is associated with dryness, atrophy, fine wrinkling, poor healing, and hot flashes. Epidermal thinning, declining dermal collagen content, diminished skin moisture, decreased laxity, and impaired wound healing have been reported in postmenopausal women. This article reviews the effects of declining estrogen levels on the skin and the effects of estrogen supplementation.

LEARNING OBJECTIVE

At the conclusion of this learning activity, participants should be familiar with the pathways of estrogen synthesis, sites of estrogen receptors, age-dependent variations in serum estrogen concentration, the changes seen in postmenopausal skin, and the effects of estrogen supplementation.

The neurotrophin receptor p75NTR mediates early anti-inflammatory effects of estrogen in the forebrain of young adult rats

BACKGROUND

Estrogen suppresses microglial activation and extravasation of circulating monocytes in young animals, supporting an anti-inflammatory role for this hormone. However, the mechanisms underlying estrogen's anti-inflammatory effects, especially in vivo, are not well understood. The present study tests the hypothesis that anti-inflammatory effects of estrogen are mediated by the pan-neurotrophin receptor p75NTR. Previously, we reported that estrogen attenuated local increases of interleukin(IL)-1beta in the NMDA-lesioned olfactory bulb, while further increasing NGF expression.

RESULTS

The present studies show that this lesion enhances expression of the neurotrophin receptor p75NTR at the lesion site, and p75NTR expression is further enhanced by estrogen treatment to lesioned animals. Specifically, estrogen stimulates p75NTR expression in cells of microvessels adjacent to the lesion site. To determine the role of this receptor in mediating estrogen's anti-inflammatory effects, a p75NTR neutralizing antibody was administered at the same time the lesion was created (by stereotaxic injections of NMDA) and specific markers of the inflammatory cascade were measured. Olfactory bulb injections of NMDA+vehicle (preimmune serum) increased IL-1beta and activated the signaling molecule c-jun terminal kinase (JNK)-2 at 6 h. At 24 h, the lesion significantly increased matrix metalloproteinase (MMP)-9 and prostaglandin (PG)E2, a COX-2 mediated metabolite of arachadonic acid. All of these markers were significantly attenuated by estrogen in a time-dependent manner. However, estrogen's effects on all these markers were abolished in animals that received anti-p75NTR.

CONCLUSION

These data support the hypothesis that estrogen's anti-inflammatory effects may be, in part, mediated by this neurotrophin receptor. In view of the novel estrogen-dependent expression of p75NTR in cells associated with microvessels, these data also suggest that the blood brain barrier is a critical locus of estrogen's neuro-immune effects.

Modulation of cardiac mast cell-mediated extracellular matrix degradation by estrogen

There are fundamental differences between males and females with regard to susceptibility to heart disease. Although numerous animal models of heart failure have demonstrated that premenopausal females are afforded cardioprotection and, therefore, fare better in the face of cardiac disease than their male counterparts, many questions as to how this occurs still exist. Recently, we showed that 1) increased mast cell density is associated with adverse ventricular remodeling and 2) chemically induced mast cell degranulation using compound 48/80 resulted in remarkable changes in matrix metalloproteinase (MMP) activity, cardiac collagen structure, and cardiac diastolic function in normal male rats. With the known gender differences in cardiac disease in mind, we sought to examine the effects of chemically induced cardiac mast cell degranulation in isolated, blood-perfused hearts of intact female rats, ovariectomized female rats, and ovariectomized female rats treated with 17β-estradiol. In response to mast cell degranulation, no significant differences in cardiac function, MMP-2 activity, or collagen volume fraction were observed between intact female rats and ovariectomized female rats treated with estrogen. In the ovariectomized female group, a significant rightward shift in the left ventricular pressure-volume relation, accompanied by a marked 133% increase in active MMP-2 values over that in the intact female group, was noted after treatment with compound 48/80 ( P ≤ 0.05), along with a significant reduction in collagen volume fraction below control (0.46 ± 0.23 vs. 0.73 ± 0.13%, P ≤ 0.05). These findings indicate that estrogen's cardioprotective role can be partially mediated by its effects on cardiac mast cells, MMPs, and the extracellular matrix.

Roles of estrogen receptor, progesterone receptor, p53 and p21 in pathogenesis of pelvic organ prolapse

The aim of this study is to compare the levels of estrogen receptor (ER), progesterone receptor (PR), p53 and p21 between pelvic organ prolapse (POP) and control groups in order to evaluate their roles in pathogenesis of POP, and to find out the relationship among these proteins. Through the year of 2002, uterosacral ligaments were obtained from 20 prolapsus and 24 non-prolapsus hysterectomized uteruses. ER, PR, p53, and p21 proteins were extracted by Western blot analysis and relative levels of proteins were compared by Student t-test and Pearson correlation coefficient. P value <0.05 was considered statistically significant. All patients were postmenopausal and had never taken hormone replacement therapy. ER, PR, p53, and p21 were significantly lower in the study than control group (p<0.0001). Positive correlations were found among all proteins in the prolapse group. Further researches are needed to elucidate the interrelationship among these proteins and their precise roles in pathogenesis of POP.

Estrogen increases collagen I and III mRNA expression in the pelvic support tissues of the rhesus macaque

OBJECTIVE

Our aim was to study the effect of estradiol and raloxifene on collagen synthesis, by measuring the expression collagen I and III mRNA.

STUDY DESIGN

Nineteen nulliparous young adult rhesus macaques underwent oophorectomy and were treated for 5 months with estradiol alone, raloxifene, or no hormone. Tissue samples were acquired from the lateral vaginal wall, and included the paravaginal attachment and levator ani muscle. Expression of mRNA for collagen I and III was measured by in situ hybridization.

RESULTS

Estradiol increased mRNA for collagen I and III compared with no hormone and raloxifene treatment (ANOVA, P < .05). Collagen mRNA was localized to fibroblasts in the vaginal connective tissue and the connective tissue investments of striated muscle. Collagen mRNA was not expressed in epithelial, smooth, and striated muscle cells.

CONCLUSION

Estrogen, but not raloxifene, increases collagen gene transcription and indicates stimulation of collagen synthesis in pelvic floor connective tissues.

Ovariectomy reduces the gelatinolytic activity and expression of matrix metalloproteinases and collagen in rat molar extraction wounds

Osteoporosis is commonly associated with estrogen deficiency. However, the mechanisms by which the lack of this hormone causes bone loss are poorly understood. The bone structure of the oral cavity seems to be affected by estrogen deficiency, since a delayed healing process after tooth extraction has been observed after ovariectomy in rats. The aim of this study was to describe the effect of the absence of estrogen on the expression and activity of matrix metalloproteinases (MMC)-2 and -9 and expression of types I and III collagens in the alveolar granulation tissue of young female rats after tooth extraction. Sixty-six, four-week-old female rats underwent bilateral ovariectomies (OVX) or sham operations. Three weeks later, both first and second mandibular molars were extracted and the animals were killed by cervical dislocation 3, 5, or 7 days after tooth extraction. The granulation tissues were collected from the extracted alveolar sockets and used for zymographic, Western blot, or reverse transcription polymerase chain reaction (RT-PCR) analysis. There was a gradual increase on the expression of all studied proteins as well as MMP-2 and -9 activities in the periods after surgery. In contrast, OVX animals showed a significant decrease in the gelatinolytic activities and expression of MMP-2 and -9 and types I and III collagens. The results presented here in suggest that the absence of estrogen may possibly contribute to the delayed alveolar wound healing by interfering with the extracellular matrix turnover.

Basic science and translational research in female pelvic floor disorders: proceedings of an NIH-sponsored meeting

AIMS

To report the findings of a multidisciplinary group of scientists focusing on issues in basic science and translational research related to female pelvic floor disorders, and to produce recommendations for a research agenda for investigators studying female pelvic floor disorders.

METHODS

A National Institutes of Health (NIH)-sponsored meeting was held on November 14-15, 2002, bringing together scientists in diverse fields including obstetrics, gynecology, urogynecology, urology, gastroenterology, biomechanical engineering, neuroscience, endocrinology, and molecular biology. Recent and ongoing studies were presented and discussed, key gaps in knowledge were identified, and recommendations were made for research that would have the highest impact in making advances in the field of female pelvic floor disorders.

RESULTS

The meeting included presentations and discussion on the use of animal models to better understand physiology and pathophysiology; neuromuscular injury (such as at childbirth) as a possible pathogenetic factor and mechanisms for recovery of function after injury; the use of biomechanical concepts and imaging to better understand the relationship between structure and function; and molecular and biochemical mechanisms that may underlie the development of female pelvic floor disorders.

CONCLUSIONS

While the findings of current research will help elucidate the pathophysiologic pathways leading to the development of female pelvic floor disorders, much more research is needed for full understanding that will result in better care for patients through specific rather than empiric therapy, and lead to the potential for prevention on primary and secondary levels.

Diet as a risk factor for the development of stress urinary incontinence: a longitudinal study in women

OBJECTIVE

To assess the association between diet and the onset of stress urinary incontinence (SUI) in women aged 40 y plus.

DESIGN AND SETTING

The Leicestershire MRC Incontinence Study - a prospective longitudinal study of the prevalence, incidence and aetiology of urinary symptoms.

SUBJECTS AND METHODS

A total of 5816 women aged 40 y plus and living in the community. Urinary symptoms were reported in a postal questionnaire at baseline and at 1-y follow-up. Dietary intake was assessed in a food frequency questionnaire at baseline.

RESULTS

Intakes of total fat, saturated fatty acids and monounsaturated fatty acids were associated with an increased risk of SUI onset 1 y later. Of the micronutrients studied, zinc and vitamin B12 were positively associated with SUI onset.

CONCLUSION

The results from this prospective study suggest there may be an aetiological association between certain components of the diet and the onset of SUI. The findings need confirming and possible mechanisms to explain these associations need further investigation.

The effect of hormone therapy and raloxifene on serum matrix metalloproteinase-2 and -9 in postmenopausal women

OBJECTIVE

The aim of the study was to investigate the effect of continuous-combined hormone therapy and raloxifene on the total and active forms of serum matrix metalloproteinase (MMP) -2 and -9.

DESIGN

The study was double-blinded, with a placebo run-in period of 28 to 50 days. Twenty-eight women received either 17beta-estradiol 2 mg + norethisterone acetate 1 mg (E2/NETA) or raloxifene HCL 60 mg for a period of 6 months. Total and active forms of MMP-2 and -9 were estimated at baseline and at month 6.

RESULTS

Total MMP-2 increased significantly in both E2/NETA and raloxifene groups (raloxifene baseline: 278.1 +/- 18.1 ng/mL; 6 months: 303.1 +/- 29.9 ng/mL, P = 0.008) (E2/NETA baseline: 281.9 +/- 27.5 ng/mL; 6 months: 298.8 +/- 12.7 ng/mL, P = 0.025). Similarly, both treatments increased the active MMP-2 fraction, although only the raloxifene-associated increase acquired significance (raloxifene baseline: 24.9 +/- 8.6 ng/mL; 6 months: 31.6 +/- 15.3 ng/mL, P = 0.045) (E2/NETA baseline: 21.7 +/- 5.7 ng/mL; 6 months: 27.4 +/- 5.8 ng/mL, P = 0.128). Total as well as active fractions of MMP-9 were not significantly affected by either treatment.

CONCLUSIONS

Both E2/NETA and raloxifene increased the total and active MMP-2 serum levels. MMP-9 was not significantly affected by either regimen. Larger, long-term clinical trials are needed to elucidate the effect of HT and raloxifene on MMPs and the possible clinical implications for cardiovascular health.

Estrogen enhances cystatin C expression in the macaque vagina

Cystatin C is a secreted inhibitor of cysteine proteinases that participates in extracellular matrix remodeling. Whether hormones affect its expression in the vagina was unknown. Consequently, we examined the effects of estradiol (E(2)), progesterone (P), and raloxifene on vaginal cystatin C in rhesus macaques. In experiment 1, ovariectomized animals were treated sequentially with E(2) (14 d) and E(2) + P (14 d) to induce 28-d menstrual cycles. Vaginal samples were collected on d 6, 8, 14, and 28 of the induced cycle. Some cycled animals were deprived of both E(2) + P for 28 d. In experiment 2, ovariectomized animals were treated for 5 months with E(2) alone, E(2) + P, raloxifene, or left untreated. Total RNA from the vaginal wall was analyzed for the cystatin C transcript with a commercially prepared cDNA array and semiquantitative RT-PCR. Vaginal cryosections were analyzed by in situ hybridization for cystatin C transcript and by immunocytochemistry for the protein. E(2) treatment significantly (5-fold; P < 0.05) increased expression of cystatin C transcript over the levels in the hormone-deprived controls, and cotreatment with P (E(2) + P) blocked this effect. Raloxifene treatment did not affect cystatin C expression. In situ hybridization and immunocytochemistry revealed that cystatin C was localized in fibroblasts and smooth muscle cells throughout the vaginal wall but not in smooth muscle cells of arteries or levator ani myocytes. In summary, E(2) increased vaginal cystatin C expression in the fibroblasts and smooth muscle bundles, P suppressed this effect, and raloxifene had no effects on cystatin C. Elevated cystatin C, by suppressing cysteine proteinase activity, may strengthen the vaginal wall and mitigate the potential for pelvic floor prolapse.

Increased Expression of Matrix Metalloproteinases in the Uterine Cervix of Postmenopausal Women

OBJECTIVE.: To determine whether atrophy of the uterine cervix in menopausal women is associated with an increased expression of matrix metalloproteinases (MMP), a decrease in their counter regulatory proteins (tissue inhibitors of matrix metalloproteinase [TIMP]), and a decrease in type I collagen. MATERIALS AND METHODS.: A pilot study was performed on cervical stroma harvested from 10 premenopausal and 9 postmenopausal women undergoing a hysterectomy. The amount of pro-MMP-2 and pro-MMP-9 in protein extracts from the two groups was compared by gelatin zymography. The membrane-type (MT)1-MMP, TIMP-1, and TIMP-2 were quantitated by Western immunoblotting. Total collagen was estimated by measuring hydroxyproline content. A primary fibroblast culture was developed to study estrogen regulation of MMP expression in vitro. RESULTS.: Pro-MMP-2 and pro-MMP-9 were increased in postmenopausal extracts. No difference in the amount of MT1-MMP, TIMP-1, TIMP-2, or total collagen was detected. In primary cervical fibroblast cultures, only active MMP-2 was suppressed by estrogen. CONCLUSIONS.: The protein expression of pro-MMP-2 and pro-MMP-9 is increased in cervical stroma of postmenopausal women relative to premenopausal women.

Aetiology and pathogenesis of benign prostatic hyperplasia

PURPOSE OF REVIEW

Prostatic hyperplasia predominantly involves the stromal compartment of the gland and affects more than 70% of men of 70 years or older with or without obstructive symptoms of benign prostatic hyperplasia. A consensus view is emerging concerning the factors and control systems that modulate cell proliferation and connective tissue biology in the prostate. The purpose of this review is to discuss some of the recent work contributing to the latter in the context of the aetiology of benign prostatic hyperplasia.

RECENT FINDINGS

Studies over the last 3-5 years have identified transforming growth factor beta, fibroblast growth factor and insulin-like growth factor family members as key regulators of cell proliferation and extracellular matrix turnover with interrelated activities. Recently, oestrogens, adrenergic signalling and inflammatory processes have been shown to impact and potentially perturb the balance between the activities of the above factors. These agents are all subject to alteration with age and as such are candidates for potential triggers of the initiation of stromal hyperplasia.

SUMMARY

The current model for the control and dysregulation of prostatic stromal growth is discussed in relation to the pathogenesis of benign prostatic hyperplasia and future directions for research.